doc: mention git node backport
Ref: https://github.com/nodejs/node/pull/44247#issuecomment-1256613382
cc: @richardlau @nodejs/releasers
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Ref: https://github.com/nodejs/node/pull/44247#issuecomment-1256613382
cc: @richardlau @nodejs/releasers